1. Field of the Invention
The present invention relates to a probe device and more particularly, to a vertical probe device, which facilitates the performance of a maintenance work without causing damage to each probe of the probe device.
2. Description of the Related Art
FIG. 1 shows a vertical-type probe card 1 according to the prior art. According to this design, a circuit board 10 of the vertical-type probe card 1 has multiple transmission lines 11 electrically connected to a probe set 12. The probe set 12 comprises an upper guide plate 121, a lower guide plate 122, a probe holder plate 123, and a plurality of probes 120. The upper guide plate 121, the lower guide plate 122 and the probe holder plate 123 each have a plurality of probe holes for receiving the probes 120. During installation, the probe holder plate 123 is held at a predetermined elevation relative to the lower guide plate 122, and then the probes 120 are respectively inserted through the probe holder plate 123 and the lower guide plate 122, and then the upper guide plate 121 is covered on the probe holder plate 123 to keep the probes 120 standing. Each of the probes 120 has an upper end protruding over the top side of the upper guide plate 121 and electrically connected to the transmission line 11 or other signal line on the circuit board 10, and a bottom probe tip protruding over the bottom side of the lower guide plate 122 for probing ICs in a wafer level testing. Because the probe holder plate 123 is provided for holding the probes 120 to be inserted through and aligned with the respective probe holes of the guide plate 121 and 122, it is designed to have a certain looseness relative to each of the probes 120. In addition, by means of the structure of a free space defined between the upper guide plate 121 and the lower guide plate 122 for allowing displacement of the body portion of each of the probes 120, the bottom probe tip of each of the probes 120 can flexibly be adjusted to the same probing plane when all of the probes 120 press on the testing ICs at the same time. As a result, the probe set 12 effectively eliminates the anti-force against from the stressed ICs and prevents damage to any of the probes 120, and therefore ensures an optimal contact of the vertical probe device 1 with all ICs at the test wafer.
In actual application, replacement or repair of a maintenance work is necessary for probes of a probe device after a long term test engineering. During a maintenance work of the probe set 12, the upper guide plate 12 must be taken away and then the damaged or worn probes 120 must be pulled out from the probe holder plate 123 and the lower guide plate 122 for replacement or repair. However, because the probe holder plate 123 is covered by the upper guide plate 121 without fixing to any structures of the probe set 12, it may be lifted with the upper guide plate 121 by the adhesion force induced by taking away the upper guide plate 12 in the maintenance work. As a result, the relative probes 120 standing on the lifted portion of the probe holder plate 123 are forced to be pulled out from the lower guide plate 122, thus a rework of inserting those still good probes 120 into the probe holder plate 123 and the lower guide plate 122 will be necessary. Therefore, this design requires much labor and time in maintenance. Further, once the probe holder plate 123 is lifted, the correspondingly lifted probes 120 may somewhat be distorted and/or even damaged, thus the extra cost must be paid.
FIG. 2 shows a Hybrid-buckling beam probe device 20 constructed according to US patent publication No. 2006/0066328. According to this design, a template 32 provided as the probe holder plate 123 of the aforesaid prior art is adhered to the top side of a raised boss formed above a lower die 28. Therefore, the template 32 is kept in place during the maintenance engineering to open an upper die to repair or replace the damaged or worn probes 36. However, because the template 32 is affixed to the lower die 28, it cannot provide the certain looseness and flexibility to the relative probes 36 as the aforementioned probe holder plate 123 of the vertical probe device 1. At the moment the probes 36 touch the test devices on a semiconductor wafer, the probes 36 receive a forward stress of the anti-force against from the probing devices with limitation to release out, thereby resulting in high possibility of being damaged and shortening the lifetime of the probes 36. Therefore, this design of Hybrid-buckling beam probe device is still not satisfactory in function.